On-Grid PV System Design

Author:Source:Datetime: 2016-09-14 10:26:21

And On-Grid systems is the fastest growing mode of solar photovoltaic applications. With the rapid development of BIPV, a variety ofsolar power portable generation technology it has been widely used. Photovoltaic power generation include several forms as follows:

First, we introduce the network and determine the best angle of the PV system.

Grid-connected photovoltaic power supply systems and independent photovoltaic system has different characteristics, there is in sunlight, the solar power generation system to the grid, and in rainy days or at night photovoltaic power supply system can not meet the load needs time and buy electricity from the grid. Such does not exist due to inclination selection improper waste generation summer and winter on the load power shortage problem. In grid-connected photovoltaic systems we need to be concerned only problem is how to choose the best angle, so that the solar cell module maximum annual power generation children. The inclination is generally the local latitude.

For any form of the above-described grid-connected PV systems, the best angle options are required to consider the actual situation, we need to consider limiting the solar battery module installation site, especially for the now rapidly growing building integrated photovoltaic (BIPV) project . Component selection dip also consider the aesthetics of the building, we need to be based on actual needs to adjust the inclination of small-scale, and this adjustment will not result in significant reduction of solar radiation absorbed. For pure grid-connected solar pwoer system, the system does not use lifePo4 batteries, electrical energy generated by the solar cell module and direct people power grid, the system directly to the power grid to provide electricity. The system uses a grid-connected inverter is the way of the inverter, so the system does not exist and the lifePo4 battery capacity of the solar cell module design. Scale PV system depends on a large investment.

At present, many grid system uses UPS functions have grid-connected photovoltaic system, which uses a lifePo4 batteries, so the power outage, you can use the lifePo4 battery to power the load, but also can reduce the impact of power outages on the grid. System battery capacity can be selected relatively small, because the battery only when the power grid failure, taking into account the actual reliability of the power supply grid, the number of self-sufficiency days of battery can be selected 12 days? The system normally uses Dual inverter is working in parallel mode.
① Mains and solar power portable generatro work in parallel. For local load electricity if the solar modules produce sufficient load used in solar cell modules to power the load, while the excess energy back to the grid.

② If the power of the solar modules produce enough, it will automatically enable the load to the local mains power supply, electricity can also automatically to recharge the battery, ensure that the battery is long-term floating state, extend lifePo4 battery life.

③ If the mains fails, the mains failure or substandard quality of electricity supply, load voltage exceeds the acceptable range, the system will automatically disconnect from the mains, turn into a stand-alone mode, the lifePo4 battery and inverter to load. Once the electricity is restored, the voltage and frequency are within the allowed return to normal state, the system will disconnect the battery, turn into grid mode.